Hello Alex，
I do not registered the dll with regsvr32, I can sure. In the Win XP system environment, PDFDemo.exe can work well only with PDFXEditCore.x86.dll and Resources.dat and PDFDemo.exe.manifest and PDFXEditCore.x86.X.manifest.
I attach the screenshots.
After trying, it only works under the xp system and not the 32-bit system. I was sorry to have directly determined that it was a 32-bit system.

Please use quotes only to mark some block of the previous post if needed, not as a reply.
As for the default application setting - search for it for example on google - this is not a SDK question.

Cheers,
Alex

Hello Alex,
Thanks for your reply., I'll do as you say.But what I want to ask is the invocation of the file association interface.
I find the cmd.help.fileAssoc command in FullDemo sample, But the effect of executing it is different from what he expressed.

Hello Alex,
Give me a hand, please.
If I add several different watermarks, how do I distinguish them to delete the specified ones?
what I want to know is how to implement it in C++ code
Another is that I want to delete the watermark on each page.
As shown in the figure：

Yes, but the watermark ID is a timestamp generated automatically when the watermark is added. For example D:20190415152354+01'00'. There is no direct way of obtaining it rather then going to the document's structure level and that is not a simple matter.

Cheers,
Alex

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